Since a device using an organic semiconductor does not require particular film forming conditions as compared to an inorganic semiconductor device according to the related art, this device may form a semiconductor thin film on various substrates or form a film at room temperature, such that this device is expected to decrease cost or implement flexibility by forming a thin film on a polymer film, or the like.
An organic semiconductor material has been widely used in devices or apparatus including, for example, an organic field-effect transistor (OFET), an organic light emitting diode (OLED), a photo detector, a photovoltaic (PV), a sensor, a memory device, and a logical circuit.
In order to manufacture a more various and cheap electronic device, organic semiconductor materials have been developed. Currently, as the organic semiconductor material, polyacene compounds such as anthracene, tetracene, pentacene, and the like, have been widely studied together with polyphenylenevinylene, polypyrrole, polythiophene, and oligothiophene. In these polyacene compounds, as a length of a chain is extended, a π system is widened, and a large orbital overlap is formed between molecules adjacent to each other, such that charge mobility is expected to be improved.
Meanwhile, among organic compounds having high charge mobility, a compound having a benzene-thiophene fused ring and a naphthalene-thiophene fused ring has been suggested, but it is difficult to introduce thiophene in naphthalene through organic synthesis, such that the compound having the naphthalene-thiophene fused ring is not a real material, but only a synthesizable structure thereof has been mentioned (Chem. Eur. J., 2006, 12, 2037-2080).
Recently, among the compounds having this naphthalene-dithiophene fused ring, a compound having the following structure has been disclosed in International Patent Laid-Open Publication No. WO 2010-058692, but solubility and electric properties may be also limited due to limitation in a substituent substituted in a moiety of the naphthalene-dithiophene fused ring, which is a factor capable of affecting physical properties of the material, or the like.

[In Chemical Formula, Z is S or Se, and R is one selected from hydrogen, an alkyl group, and a phenyl group.]
Meanwhile, since most of the polyacene compounds require high crystalline structure in order to provide molecular orientation causing excellent charge mobility and are slightly insoluble in a general solvent, most of the polyacene compounds have been vapor-deposited. This vapor deposition is expensive and requires a complicated apparatus, such that development of an organic semiconductor material suitable for a solution-based process capable of decreasing amounts of materials used in production and consumed energy has been demanded.
Therefore, in the present invention, a compound having a naphthalene-dithiophene fused ring having excellent charge mobility, and including various substituents introduced at 4,9-positions of the compound to thereby be advantageous for polymer synthesis through polymerization, and having high solubility to thereby be advantageous for the solution-based process, and a polymer compound containing this compound as a monomer was synthesized.